Method for manufacturing a wire stent coated with a biocompatible fluoropolymer

Abstract

A method for manufacturing a stent includes heating a plurality of wire strands to impart a desired shape to the wire strands, coating each wire strand with a biocompatible polymer in an extruder to produce a plurality of coated wire strands, and interlacing the coated wire strands to form a stent.

What is claimed is: 
     
       1. A method for making a stent comprising:
 heat treating a plurality of wire strands; 
 coating the wire strands with a biocompatible fluoropolymer in an extruder to produce a plurality of coated wire strands; 
 spooling the coated wire strands; and 
 interlacing the coated wire strands from separate spools into a tightly held together monolayer integrated tubular shape, the tubular shape adapted to have axial and radial compressibility for insertion into a cardiovascular, vascular or non-vascular system of a human body. 
 
     
     
       2. The method as defined in  claim 1  wherein the wire strands include a material selected from the group consisting of stainless steel, tungsten, titanium, nickel-titanium alloy, gold, silver or a combination thereof. 
     
     
       3. The method as defined in  claim 1  wherein the fluoropolymer is selected from the group consisting of PTFE, ePTFE, FEP or a combination thereof. 
     
     
       4. The method as defined in  claim 1  wherein at least one wire strand is employed in a coil pattern. 
     
     
       5. The method as defined in  claim 1  wherein interlacing the coated wire strands is carried out in a knitting machine. 
     
     
       6. The method as defined in  claim 5  wherein a brake mechanism on a spool supplying one coated wire strand causes the spool to supply such coated wire stand at a slower rate than other spools supplying the other coated wire strands. 
     
     
       7. The method as defined in  claim 1  wherein textile strands are interlaced between the coated wire strands. 
     
     
       8. The method as defined in  claim 7  wherein the textile strands include a material selected from the group consisting of polyester, polypropylene, polyethylene, polyurethane, polytetrafluoroethylene or a combination thereof. 
     
     
       9. The method as defined in  claim 1  wherein at least one wire strand is preheated in an oven to impart an intended shape prior to coating. 
     
     
       10. The method as defined in  claim 1  wherein the tightly held together monolayer integrated tubular shape allows for the exuding of blood for proper lumen wall function. 
     
     
       11. A method for making a stent comprising:
 heating a plurality of wire strands to impart a desired shape to the wire strands; 
 coating each wire strand with a biocompatible polymer in an extruder to produce a plurality of coated wire strands; and 
 interlacing the coated wire strands to form a stent. 
 
     
     
       12. The method as defined in  claim 11  further including regulating the speed of the wire strands in the extruder to provide a uniform coating. 
     
     
       13. The method as defined in  claim 12  wherein interlacing includes braiding the coated wire strands in a braiding machine. 
     
     
       14. The method as defined in  claim 13  further including spooling the coated wire strands onto spools, and wherein braiding includes removing the coated wire strands from the spools while braiding the coated wire strands in the braiding machine. 
     
     
       15. The method as defined in  claim 14  further including regulating the speed of at least one of the spools at a slower rate than other spools. 
     
     
       16. The method as defined in  claim 15  further including incorporating a fabric material between the braided, coated wire strands. 
     
     
       17. The method as defined in  claim 16  further including preparing ends of the wire strands to prevent fraying. 
     
     
       18. The method as defined in  claim 11  wherein interlacing includes knitting the coated wire strands in a knitting machine. 
     
     
       19. A method for making a stent comprising:
 coating a plurality of wire strands with a biocompatible polymer and an adhesive in an extruder to produce a plurality of coated wire strands; 
 heating the coated wire strands to activate the adhesive; and 
 interlacing the coated wire strands to produce a stent. 
 
     
     
       20. A method for making a stent comprising:
 interlacing a plurality of wire strands into a desired shape; 
 heating the wire strands in the desired shape; 
 removing the wire strands from the desired shape; 
 coating the wire strands with a biocompatible polymer; and 
 interlacing the wire strands to form a stent.